SHANGHAI has been experiencing some of its most serious and long-lasting air
pollution in months, as well as weather conditions that have contributed to
thick clouds and a haze that has grounded some flights and led to vehicular
crashes which killed at least one person and injured dozens.

Some expressways were closed from 3am to 9am yesterday because fog and haze
created dangerous driving conditions, causing vehicles to line up for
kilometers, according to the Shanghai highway authority.

Serious pollution that started on Saturday may continue today, though
conditions may improve tomorrow, forecasters said.

The PM2.5 readings of tiny airborne particles smaller than 2.5 micrometers
started to rise on Saturday afternoon and exceeded 300 micrograms per cubic
meter yesterday morning, four times the standard for good air quality, which is
75 micrograms per cubic meter, according to the Shanghai Environmental
Monitoring Center.

All 10 monitoring stations for PM2.5 across Shanghai turned on a purple light
to indicate the second-highest level in the six-color alert system, meaning
serious air pollution. That means those with some health conditions such as
pulmonary problems may want to stay indoors when possible.

The city's 24-hour average reading for PM2.5 ending yesterday afternoon was
above 220 micrograms per cubic meter, the highest in the past six months.

The readings started to drop in the afternoon and could improve with some
drizzle tonight and a change in the wind, but reduction has been slow, the
center said. The air pollution conditions should clear up more tomorrow. The
duration of the pollution conditions is the longest in the past five months,
according to the center.

A cold front has brought pollution and a regional haze with it, and the city
also has been under a static pressure field with only light winds and high
humidity, which has helped trap pollution, the center said.

Colder temperatures on way

The city is expected to get chillier this week with the arrival of more cold
fronts, according to the Shanghai Meteorological Bureau.

Today is forecast cloudy to drizzly, with a low of 16 degrees Celsius to a
high of 21. The highs should drop to around 18 degrees from tomorrow to Friday
and the low should go as low as 10 degrees on Thursday.

"The city is on a trend of getting colder, but it has been gradual," said
Zhang Ruiyi, a chief service officer of the weather bureau. Zhang said tomorrow
should be more clear, just partly cloudy for the rest of the week.

The fog and haze may have contributed to a number of crashes, traffic
officials said.

One person died and five others were injured when three vehicles were
involved in a rear-end crash on the G60 Expressway in the fog yesterday morning,
police said.

A truck hit a sedan, which hit another truck in the front, witnesses said.
The driver of the first truck died at scene while the injured, including a
Spaniard riding in the sedan, were rushed to the hospital. They were reported to
be stable yesterday afternoon.

Around 5am, a No. 117 bus hit a sedan on Xincun Road near Shuiquan Road in
Putuo District, during a left turn. A passenger in the sedan was injured, said
Xinmin.cn.

Around 7am, a taxi and a minibus involved in a crash overturned on Nanpu
Bridge.

Around 12:40pm, a bus rear-ended a truck on the Bao'an Expressway in Jiading
District, injuring 44 people, four of whom were in critical condition, officials
said.

The truck, carrying a full load of steel plates, pulled over on a bridge on
Bao'an Road after a flat tire. The bus of the Jiating Line, traveling at high
speeds, crashed into the rear of the truck. The driver of the bus may have to
have a leg amputated, doctors said.

At least 70 flights were canceled and 27 delayed at the city's Hongqiao and
Pudong international airports. The airports were able to resume normal
operations in the afternoon as temperatures rose and the fog
lifted.